We’re just hours away from Apple’s much-anticipated media event in San Francisco where it’s expected to reveal the latest iteration of its iPhone – but of course, until Tim Cook actually holds up the new device on stage at the Yerba Buena Center for the Arts on Wednesday, the rumor mill will keep on turning.

Prior to the unveiling of a new iteration of a popular device, speculation understandably swirls around how its physical look might alter – will it be bigger, smaller, taller, shorter, thicker, thinner, heavier, lighter? Or, perhaps, pretty much the same?

With the iPhone 5 (or whatever Apple has decided to call it), the latest reports suggest the handset is about to undergo its most radical redesign since coming on the market five years ago.

More information is circulating pointing to a phone that will be both taller and slimmer. MacRumors reader Michael Rou posted a photo (below) on his site showing pre-production cases for Apple’s expected iPhone 5 and iPad Mini devices, made by case manufacturers based on leaked specifications from Foxconn factories in China, where the handset is being assembled. With the current iPhone placed inside the new case, it’s clear that the next version will be taller, though retaining its 2.31-inch width, giving the appearance of a ‘stretched’ iPhone with a widescreen display.

Different images from Know Your Mobile also show a set of cases that are markedly longer than what’s available for the existing iPhone. The photos (one shown below) were obtained from mobile accessories company Mobile Fun. “They’re genuine leather pouches – one of the images even shows the size difference compared to the iPhone 4,” Mobile Fun told KYM. “We’re highly confident that these cases show that the size of the iPhone 5 will be taller than the iPhone 4.”

With the iPhone’s 3.5-inch screen starting to look a little on the small side when compared to its competitors’ offerings, there’s little doubt the next version will sport a larger display – the main question has been whether Apple would opt to push the viewable screen to the edges of the current design, or introduce a taller model. Based on all these images, it appears to be the latter.

As for its thickness, iResQ (via tech2) used received parts to build the casing of the next phone, with one of its pictures (below) showing Apple’s next handset to be marginally slimmer than its predecessor, likely due to the incorporation of a new in-cell display, which is thinner than a conventional LCD touchscreen.

Soon the Apple rumor mill will once again rest. All will be revealed shortly. Deep breaths now, Apple fans, deep breaths….